SUBCHRONIC STUDIES OF TRIPROLIDINE IN FISCHER 344 RATS

Triprolidine, used extensively as an antihistamine, was studied for su bchronic toxicity by administration as an admixture in the diet to mal e and female Fischer 344 rats at dosage levels of 0, 156, 312, 625, 12 50, and 2500 parts per million (ppm) for 14 days and in a second study at 0, 250, 500, 1000, 2000, and 4000 ppm for 90 days. In the 14-day s tudy, the only sign of toxicity observed either clinically or histolog ically was a reduction of final body weights (less than 10%) of both m ale and female rats in the 2500 ppm dosage group associated with reduc ed food consumption. In the 90-day study, final body weights were redu ced, compared to controls, at the higher dosage levels with 4000 ppm r esulting in a 20% and 13.4% reduction in males and females, respective ly. Target organs were identified as the liver with hepatic fatty chan ge and the parotid salivary gland, which exhibited treatment-related c ytoplasmic alterations of the acinar cells. Males were more susceptibl e than females to both of these effects. These results indicate that r ats would tolerate 2000 ppm triprolidine in a 2-year chronic bioassay without significant shortening of life span.